Battery powered charging/USB hub

[Ian Stirling]

Frank Coenen wrote:
> Somehow that doesn't sound right to me. Like in the movies, when they 
> try to hack a computer: there is always some OVERWRITE command, that 
> doesn't require a password but will grand you access to all the files.
> 
> Same applies here. Why put a safety-measure in place if you plan to 
> ignore it anyway? ;-)

Because if you have 5V connected, but the host is not talking in host 
protocol, that itself violates the USB protocol to a degree.
This is not a safety issue.

All USB hosts have some form of current limiting.
Worst case is that you plug something that takes 500mA into a USB port 
that can't take it, is the bus resets.

And even that wouldn't happen if the host is actively behaving as a USB 
host.
If it's not, then the bus resetting doesn't really matter so much, as 
it's not using the bus.
There are _lots_ of 'USB fan' or 'USB light''s that are out there.
These just treat the USB port as a source of 500mA.
Manufacturing a host that will die when you plug in one of these will 
lead to _lots_ of returns.